Exercise Management Obesity Chapter 25

Exercise Management OBESITY Obesity is the excessive accumulation of body fat and is associated with numerous comorbidities. Prevalence of Childhood Obesity in the United States, Prevalence of Childhood Obesity in the United States, Adult Obesity Rates Obesity Prevalence Maps

Exercise Management Obesity is a multifaceted disease, and may involve hypothalamic, endocrine, and genetic disorders, environment, and behavior. Altered insulin function may be the primary mechanism in the etiology (causation) and maintenance of obesity. Obesity is a multifaceted disease, and may involve hypothalamic, endocrine, and genetic disorders, environment, and behavior. Altered insulin function may be the primary mechanism in the etiology (causation) and maintenance of obesity. Obesity is not just about overeating. Most evidence suggest that it is a combination of caloric dense, empty calorie diets, combined with a sedentary lifestyle Obesity is not just about overeating. Most evidence suggest that it is a combination of caloric dense, empty calorie diets, combined with a sedentary lifestyle Obesity is also complicated with the prospect that humans have evolved over many millennia from hunter-gather high energy expenditure lives to low energy expenditure high calorie lives. Obesity is also complicated with the prospect that humans have evolved over many millennia from hunter-gather high energy expenditure lives to low energy expenditure high calorie lives.

Exercise Management Defining Obesity (see Table 25.1, p.193, text)

Exercise Management Altered physiological responses in obesity include: increased fasting insulin increased fasting insulin increased insulin response to glucose increased insulin response to glucose decreased insulin sensitivity, decreased insulin sensitivity, decreased growth hormone, decreased growth hormone,growth hormonegrowth hormone decreased growth hormone response to insulin stimulation decreased growth hormone response to insulin stimulation increased adrenocortical hormones (glucocorticoids, mineralocorticoids, and androgens ) increased adrenocortical hormones (glucocorticoids, mineralocorticoids, and androgens )glucocorticoids mineralocorticoidsandrogensglucocorticoids mineralocorticoidsandrogens increased cholesterol synthesis and excretion increased cholesterol synthesis and excretion decreased hormone-sensitive lipase decreased hormone-sensitive lipasehormone-sensitive lipasehormone-sensitive lipase

Exercise Management The primary difference between the identification, definition, and classification of obesity is the assessment of body fat. The following percentages of body fat are for men and women:

Exercise Management

Obesity increases not only the risk of disease but also the severity of numerous diseases. Obesity increases not only the risk of disease but also the severity of numerous diseases. The distribution of body fat may contribute more to disease than total body fat. The distribution of body fat may contribute more to disease than total body fat. Upper body fat distribution has been associated with increased risk of coronary artery disease (CAD), hypertension, hyperlipidemia, and diabetes, and hormone / menstrual dysfunction. Upper body fat distribution has been associated with increased risk of coronary artery disease (CAD), hypertension, hyperlipidemia, and diabetes, and hormone / menstrual dysfunction. Truncal adipocytes are more metabolically active than other adipocytes and secrete adipocytokines (proteins) that control other metabolic functions including: increased insulin resistance, hypertension via sodium retention, and increase sympathetic activation w/ smooth muscle hypertrophy in the vasculature. Truncal adipocytes are more metabolically active than other adipocytes and secrete adipocytokines (proteins) that control other metabolic functions including: increased insulin resistance, hypertension via sodium retention, and increase sympathetic activation w/ smooth muscle hypertrophy in the vasculature.

Exercise Management Abdominal adipocytes are associated with increased very low density lipoprotein, triglyceride, and adipose lipoprotein lipase activity. Thus, excess fat in specific deposits may contribute more to the diseases associated with obesity. Abdominal adipocytes are associated with increased very low density lipoprotein, triglyceride, and adipose lipoprotein lipase activity. Thus, excess fat in specific deposits may contribute more to the diseases associated with obesity Body fat distribution can be estimated by the measurement of waist-to-hip ratios. Body fat distribution can be estimated by the measurement of waist-to-hip ratios. The most common and most often recommended technique may be the ratio of the minimal waist to the largest gluteus The most common and most often recommended technique may be the ratio of the minimal waist to the largest gluteus

Exercise Management

Effects on the Exercise Response The obvious effect of obesity on exercise testing is low physical work capacity because of excess body weight. The obvious effect of obesity on exercise testing is low physical work capacity because of excess body weight. Because obesity is associated with other diseases, however, any of the confounding influences of these diseases may be involved in exercise testing. Because obesity is associated with other diseases, however, any of the confounding influences of these diseases may be involved in exercise testing. Social and behavioral factors associated with obesity, such as past experiences with and current fears of exercise should be considered. Social and behavioral factors associated with obesity, such as past experiences with and current fears of exercise should be considered. Prior to exercise testing, a comprehensive health and medical history should be obtained from obese patients. Prior to exercise testing, a comprehensive health and medical history should be obtained from obese patients.

Exercise Management Effects of Exercise Training Exercise training is effective in reducing body weight in Exercise training is effective in reducing body weight in moderate obesity, but may not be as effective in morbid obesity. Fat loss through exercise is more efficient for individuals with Fat loss through exercise is more efficient for individuals with upper body fat distribution. Physical activity combined with diet is more effective in fat loss than either alone. Physical exercise can: 1) preserve lean mass; 2) improve insulin sensitivity; 3) improve lipid profiles; 4) reduce blood pressure; 5) improve mood, and, possibly; 6) make positive improvements on satiety levels Physical activity combined with diet is more effective in fat loss than either alone. Physical exercise can: 1) preserve lean mass; 2) improve insulin sensitivity; 3) improve lipid profiles; 4) reduce blood pressure; 5) improve mood, and, possibly; 6) make positive improvements on satiety levels Exercise training has profound effects on glucose metabolism in both the moderately and the morbidly obese. These include Exercise training has profound effects on glucose metabolism in both the moderately and the morbidly obese. These include decreased fasting glucose decreased fasting glucose decreased fasting insulin decreased fasting insulin increased glucose tolerance increased glucose tolerance decreased insulin resistance. decreased insulin resistance.

Exercise Management Management via exercise The individual who is most likely to be successful in weight loss: is slightly or moderately obese is slightly or moderately obese has upper body fat distribution has upper body fat distribution has no history of weight cycling has no history of weight cycling has a sincere desire to lose weight has a sincere desire to lose weight became overweight as an adult. became overweight as an adult. (FYI – Pharmacology and Bariatric Surgery)

Exercise Management Recommendations for Exercise Testing (Table 25.5, p.197, also below) Evaluation of the client who is obese includes more than just exercise testing. Additional assessments include: medical and weight histories, medical and weight histories, motivation and readiness for change, motivation and readiness for change, nutrition and eating habits, nutrition and eating habits, body composition. Body composition assessment includes a measure of the extent of obesity, distribution of body fat, and a reasonable target weight. body composition. Body composition assessment includes a measure of the extent of obesity, distribution of body fat, and a reasonable target weight.

Exercise Management Recommendations for Exercise Testing The primary objective of exercise testing with individuals who are obese is developing a safe and effective exercise prescription. The primary objective of exercise testing with individuals who are obese is developing a safe and effective exercise prescription. Disease diagnosis is a secondary objective. Disease diagnosis is a secondary objective. Exercise testing should also take into consideration any comorbidities, orthopedic limitations, and current medications. Exercise testing should also take into consideration any comorbidities, orthopedic limitations, and current medications. Important considerations include the increased risk for orthopedic injury, CAD, and heat intolerance. Important considerations include the increased risk for orthopedic injury, CAD, and heat intolerance.

Exercise Management

Recommendations for Exercise Programming (Table 25.6, p.198, follows) Mode: Non-weight-bearing exercise - Walking Increase in daily living activities Resistance training Frequency: Daily or at least 5 sessions/week Duration: 30 to 60 min/day or 20 to 30 min twice daily Intensity: 50 to 70% of peak oxygen consumption (VO 2,peak). Exercise intensities of 70 to 85% of VO 2,peak can be prescribed providing the risk of injury is minimal

Exercise Management Recommendations for Exercise Programming (Table 25.6, p.198) The focus of the exercise prescription is to increase energy expenditure and minimize the risk of injury. The focus of the exercise prescription is to increase energy expenditure and minimize the risk of injury. For some patients two or more sessions per day with less duration may be more tolerable and may result in exercise at a higher intensity. For some patients two or more sessions per day with less duration may be more tolerable and may result in exercise at a higher intensity. Most important is to increase caloric expenditure at or above 2000 kcal /wk. Progression to the longer duration and total caloric expenditure should be gradual. Most important is to increase caloric expenditure at or above 2000 kcal /wk. Progression to the longer duration and total caloric expenditure should be gradual.

Exercise Management Recommendations for Exercise Programming The following considerations and guidelines are relevant for exercise programming in obese populations: Prevention of overuse injury Prevention of overuse injury Injury history Injury history Adequate flexibility, warm-up, and cool-down sessions Adequate flexibility, warm-up, and cool-down sessions Gradual progression of intensity and duration Gradual progression of intensity and duration Use of low-impact or non-weight-bearing exercises Use of low-impact or non-weight-bearing exercises Thermoregulation Thermoregulation Time of day – should be cool Time of day – should be cool Adequate hydration Adequate hydration Clothing (e.g., should be loose fitting) Clothing (e.g., should be loose fitting)

Exercise Management

End of Presentation